Databases in Practice 29 Databases In Practice 29

Databases in Practice 29 We’re now going to look at some more advanced database topics: Online & Local Databases A A SQL C C DBMS B B Data Validation D D

Databases in Practice 29 Online means the kind of databases that are used in most big websites Local means a database held inside a network to keep it secure Online & Local Databases A A

Databases in Practice 29 Client SideServer Side DatabaseWeb Server Client Online Databases A A

Databases in Practice 29 Local Databases A A

Databases in Practice 29 Local Databases A A Access restricted to staff in an organisation

Databases in Practice 29 We’re now going to look at some more advanced database topics: Online & Local Databases A A SQL C C DBMS B B Data Validation D D

Databases in Practice 29 A DBMS is software that allows you to create & use your own database It creates tables and fields and allows you to search and sort data It handles security to prevent un-authorised access It can also allow for different levels of access for different users DBMS B B

Databases in Practice 29 DBMS 6 6 Data Users Applications Hacker!

Databases in Practice 29 We’re now going to look at some more advanced database topics: Online & Local Databases A A SQL C C DBMS B B Data Validation D D

Databases in Practice 29 SQL is the language used by a DBMS to actually create & search a database It has a Data Definition Language (DDL) to set-up the tables And it has a Data Manipulation Language (DML) for updates & search queries A query is the technical name for a search SQL C C

Databases in Practice 29 Say we want the names of all VIP members In SQL we would say: SELECT Forename WHERE MemberType = VIP What would the search results be? SQL C C

Databases in Practice 29 Say we want all items priced over 50 pence... In SQL we would say: SELECT Item WHERE Price > 0.50 What would the search results be? SQL C C

Databases in Practice 29 Say we want to know what Dave Smith teaches In SQL we would say: SELECT Instrument WHERE Teacher = Dave Smith What would the search results be? SQL C C

Databases in Practice 29 SQL C C

Databases in Practice 29 We’re now going to look at some more advanced database topics: Online & Local Databases A A SQL C C DBMS B B Data Validation D D

Databases in Practice 29 Validation means checking data on input to see if it meets certain rules These validation rules check that the data is sensible (but can’t check if correct) Here are some different kinds of validation rules… Data Validation D D

Databases in Practice 29 Form group? Effort grade? Data of birth? Barcode number Height? Forename? Postcode? Phone number? Data Validation D D

Databases in Practice 29 Example Database – Exam Scores

Databases in Practice 29 Databases In Practice 29